Please tell me this is a joke. If you really want to impress him / her, when s/he reaches out a hand to shake yours, get down and genuflect.

You don't need courtroom tips, as you will be interviewing in chambers. Chambers is not a courtroom and you should not act like a lawyer in there. By and large, judges see enough of lawyers trying to act like lawyers, so just be yourself. You're eager to learn and help in any way you can.